酸性矿井水环境中矸石胶结充填体的强度演化及劣化规律  

Strength evolution and deterioration law of cemented gangue backfill body in acid mine water

作　　者：赵永辉 郭育霞 冯国瑞 ZHAO Yong-hui;GUO Yu-xia;FENG Guo-rui(College of Mining Engineering,Taiyuan University of Technology,Taiyuan 030024,China;Shanxi Province Research Centre of Green Mining Engineering Technology,Taiyuan 030024,China;Shanxi Province Coal-based Resources Green and High-efficiency Development Engineering Center,Taiyuan 030024,China;Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering,Taiyuan 030024,China)

机构地区：[1]College of Mining Engineering,Taiyuan University of Technology,Taiyuan 030024,China [2]Shanxi Province Research Centre of Green Mining Engineering Technology,Taiyuan 030024,China [3]Shanxi Province Coal-based Resources Green and High-efficiency Development Engineering Center,Taiyuan 030024,China [4]Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering,Taiyuan 030024,China

出　　处：《Journal of Central South University》2024年第5期1560-1573,共14页中南大学学报（英文版）

基　　金：Project(51925402) supported by the National Natural Science Foundation for Distinguished Young Scholars of China;Project(51974192) supported by the National Natural Science Foundation,China;Project(2022SX-TD007) supported by the Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering Project,China。

摘　　要：矸石胶结充填开采是一种重要的充填开采方法,然而,酸性矿井水会严重影响矸石胶结充填体的强度。在本研究中,将矸石胶结充填体试件分别置于不同环境(空气、水、硫酸溶液、硫酸与荷载耦合)中,测试了不同龄期试件的抗压强度、电阻率及超声波波速,监测了加载过程中试件的声发射能量数值,同时结合扫描电镜和X衍射分析不同龄期充填体的微观结构。结果表明,1)空气中与水中养护的充填体抗压强度的增长趋势随龄期的增加而逐渐减缓。硫酸溶液中的充填体强度在前90天大于空气及水中养护的充填体强度。硫酸溶液与荷载耦合作用下充填体的强度随龄期的下降速率比单一硫酸溶液作用的较为缓慢;2)不同龄期矸石胶结充填体电阻率与超声波波速与强度有较好的对应关系。受侵蚀后矸石胶结充填体的破坏形式较为多样,且在加载不同阶段表现出不同的声发射能量特征,可以将声发射能量激增作为充填体的破坏前兆;3)侵蚀产物前期填充充填体内部孔隙,提高了其强度,后期会导致充填体膨胀开裂,强度降低。施加40%应力强度比的荷载会抵抗硫酸溶液的侵蚀。本文研究结果可以为充填体的耐侵蚀设计提供参考。Cemented gangue backfill technology is an important backfill mining method.However,the acid mine water environment could seriously affect the strength of the cemented gangue backfill body(CGBB).In this study,CGBB specimens were placed in different environments(air,water,H_(2)SO_(4) solution,and H_(2)SO_(4) solution coupled with load)to test the strength,resistivity,and ultrasonic pulse velocity(UPV)of CGBB at different ages.The acoustic emission(AE)energy of the specimens during loading was monitored,and the microstructure was analyzed by scanning electron microscopy(SEM)and X-ray diffraction(XRD).Test results showed that:1)The strength of CGBB cured in air and water gradually slowed down with age.The strength of CGBB in the H_(2)SO_(4) solution was greater than that of CGBB cured in air or water in the first 90 d.The strength of CGBB under the coupling of the H_(2)SO_(4) solution and load decreased more slowly with age than that of the single H_(2)SO_(4) solution;2)The resistivity and UPV had a good corresponding relationship with the strength of the CGBB.The failure modes of the CGBB after erosion were various,and the CGBB showed different AE energy characteristics at different stages of loading.The surge of AE energy could be used as a precursor to the failure of CGBB;3)Erosion products compacted CGBB in the early stages and improved its strength.In the later stage,the CGBB cracked under the action of expansion stress and the strength decreased.Applying a 40%stress-to-strength ratio would resist the erosion of the H_(2)SO_(4) solution.The research could provide a reference for the design of the corrosion resistance of CGBB.

关 键 词：酸性矿井水 矸石胶结充填体 劣化规律 电阻率 超声波波速 声发射能量 微观结构 

分 类 号：TD823.7[矿业工程—煤矿开采]